Jack for lifting a vehicle

ABSTRACT

The invention relates to a jack, the jack comprises a base for placing on the ground and an elevator mechanism which bears against the base via a leg ( 1 ) linked to the base by a device so that the leg can pivot on the base about a horizontal axis X′X and can slide on the base along the axis, the jack being characterized in that the base ( 5 ) has a longitudinal rig ( 5   b ) with a rounded top projecting above the base, the rib defining the axis, the leg ( 1 ) is provided at its bottom end with a slide ( 8 ) made of a block of synthetic organic material engaged in the bottom end and held to the leg by a device, the slide being shaped so as to be capable of fitting astride the rib of the base with the ability to pivot on the rib about the axis and to slide along the rib, and a link device ( 9, 10, 12 ) is established between the leg and the base to hold the slide on the rib. The invention applies in particular to a jack for lifting a vehicle.

The invention relates to a jack for lifting a vehicle, the jackcomprising a base for placing on the ground and an elevator mechanismwhich bears against the base via a leg, the leg being linked to the baseby a device so that the leg can pivot on the base about a horizontalaxis and can slide on the base along the horizontal axis.

BACKGROUND

The ability of the elevator device to slide longitudinally and to pivotrelative to the base limits parasitic forces tending to twist the jackwhile the vehicle is being raised.

An embodiment of such a jack is described, for example, in publicationDE-U-8 702 290.

The present invention provides a jack that is simpler to manufacture.

SUMMARY

The jack of the invention is characterized in that:

the base has a longitudinal rig with a rounded top projecting above thebase, the rib defining the pivot axis;

the leg is provided at its bottom end with a slide made of a block ofsynthetic organic material engaged in the bottom end and held to theleg, the slide being shaped so as to be capable of fitting astride therib of the base with the ability to pivot on the rib about the axis andto slide along the rib; and

a link device is established between the leg and the base to hold theslide on the rib.

An embodiment of a jack of the invention as defined above is describedbelow, this embodiment also having other characteristics which formportions of the invention, in isolation or in combination.

In this embodiment, the link device has a shaft which passes through theleg and/or the slide parallel to the axis and which is attached to thebase so as to be capable of pivoting about the axis.

BRIEF DESCRIPTION OF THE DRAWINGS

The description refers to the figures of the accompanying drawings, inwhich:

FIG. 1 is a general view of the jack in position for inserting under acar;

FIG. 2 is a detail view of the ground-bearing end of the jack, with thevarious parts provided by the invention being shown separately toclarify the figure;

FIG. 3 is a view similar to FIG. 2 after the parts have been assembledtogether;

FIG. 4 is a section through the ground-bearing end of the jack on aplane AA containing the pivot axis;

FIG. 5 is a section on a plane perpendicular to the plane AA of FIG. 4;

FIG. 6 is a general view of the slide; and

FIG. 7 is a general view of the jack pivoted into end-of-elevationstroke position.

The jack shown in the figures is of the Y type.

DESCRIPTION

Essentially, and in conventional manner, the jack comprises an elevatormechanism constituted by a bearing leg 1 having an elevator leg 3 hingedthereto about an axis 2, a device being provided to enable the elevatorleg to pivot about the axis under the control of a handle 4 (FIG. 1).

The bearing leg 1 bears against the ground via a base 5, and theelevator leg 3 is provided with an accessory 6 enabling it to engage theunderside of a vehicle which is represented merely by a side member 7 ofits bodywork (FIG. 1).

According to the invention, the base is constituted by a metal plate 5 awhich is deformed locally, e.g. in its middle, so as to constitute alongitudinal tunnel 5 b of substantially U-shaped right section, thetunnel embodying the pivot axis X′X.

In a variant, the tunnel could be formed by a cylinder fitted to theplate, but that embodiment is less advantageous.

The bearing leg 1 has two parallel walls 1 a and 1 b, generally made ofmetal, and at the bottom end of the leg they define between them a gapin which there is engaged a block 8 made of a synthetic organic materialhaving a good sliding coefficient and good mechanical strength, e.g. ablock of polyacetal. The block is held engaged by tabs 14 formed at theends of the walls 1 a and 1 b and folded around the block after it hasbeen put into place. The tabs are shown prior to being folded in FIG. 2,and after being folded in FIGS. 3 and 5. In a variant, other fastenercould be used, e.g. adhesive.

The block is shaped to have an underface 8 e with a rounded recess (FIG.5) for placing astride the tunnel 5 b so as to be capable of pivotingforwards and backwards on the top of the tunnel and so as to capable ofsliding along the tunnel.

The block has two stops 8 a and 8 b which limit the pivot stroke of theblock (and thus of the leg) in one direction and in the other by cominginto abutment against the plate 5 a of the base (figure). The twoend-of-pivot stroke positions of the leg relative to the face correspondrespectively to the position in which the leg is inserted under the car(FIG. 1) and the maximum lift position where the leg is vertical (FIG.7).

The sliding stoke on the base of the block (and thus of the leg) isdefined in opposite directions by tabs 5 c and 5 d formed in the plateof the base in the ends of the tunnel 5 b.

The leg is linked to the base by a link device which has two parallelshafts 9 and 10, one of the shafts, 9, passing through holes 11 formedin the walls 1 a and 1 b of the leg and/or passing through the block,and the other shaft 10 passing through the tunnel 5 b, with the twoshafts being interconnected by two plates 12 or by any equivalentinterconnection.

It is possible for the shaft 9 to pass only through the metal flanks 1 aand 1 b of the leg (above the block) or to pass only through the block,however and as shown, it is preferable for the shaft to pass boththrough the leg and through the block, with the block serving as abearing for the shaft.

The shaft 9 can be continuous as shown, or else it can be discontinuous.In which case, it is constituted by two shafts, e.g. respectivelysituated to the right and to the left of the block, and each having anend that is anchored in the block.

Similarly, the shaft 10 can be continuous or it can be constituted bytwo parts that are engaged in respective opposite ends of the tunnel.

The shaft 9 and the shaft 10 can have any right section.

In the example shown, the shaft 9 is cylindrical and the shaft 10 has aright section in the form of a circular sector, but these shapes aregiven purely by way of example.

The shaft 9 carries springs 10 which urge the leg towards a positionthat is situated in the middle of its sliding stroke.

The block 8 is preferably extended laterally beyond the walls 1 a and 1b of the leg 1 by portions 8 b and 8 c which constitute covers hidingthe springs 13.

In this embodiment, according to an important aspect of the invention, alarge number of functions are performed by the block 8 of syntheticorganic material, made by molding and possibly also machined. Inparticular, from FIG. 6 which is a view of the block on its own, it canbe seen that it is in the form of a saddle having:

a re-entrant rounded surface 8 e shaped to pivot on the rib of the base;

sloping flat longitudinal sides 8 a and 8 d that rise outwards toconstitute the two stops which limit the pivot stroke of the leg on thebase;

two notches 8 f for receiving the folded tabs 14 of the metal flanks ofthe leg;

two coaxial bores 8 g and 8 h opening to the outside to receive the endsof the springs 13 and to allow the shaft 9 to pass through;

a central bore 8 i interconnecting the side bores and serving as abearing for the shaft 9; and

two extensions 8 b and 8 c which serve as covers for hiding andprotecting the springs 13. In this case, grooves 8 j and 8 k are formedbetween the central portion of the block and the covers to receive theends of the metal flanks of the leg.

The invention is not limited to being applied to a Y-type jack nor is itlimited to this particular invention described or can substitute theinvention by a functionally equivalent device.

What is claimed is:
 1. A jack for lifting a vehicle, the jack comprisinga base for placing on the ground and an elevator mechanism which bearsagainst the base via a leg (1) linked to the base by a device so thatsaid leg can pivot on the base about a horizontal axis X′X and can slideon the base along said axis, the jack being characterized in that: thebase (5) has a longitudinal rig (5 b) with a rounded top projectingabove the base, said rib defining said axis; said leg (1) is provided atits bottom end with a slide (8) made of a block of synthetic organicmaterial engaged in said end and held to the leg by said device, theslide being shaped so as to be capable of fitting astride the rib of thebase with the ability to pivot on the rib about said axis and to slidealong the rib; and a link device (9, 10, 12) is established between theleg and the base to hold the slide on the rib.
 2. A jack according toclaim 1, in which the base is constituted by a plate (5 a) which hasbeen locally deformed to constitute a longitudinal tunnel (5 b) ofsubstantially U-shaped right section on one face of the plate, saidtunnel constituting said rib.
 3. A jack according to claim 2 in whichsaid plate has cutout portions (5 c, 5 d) constituting tabs definingend-of-stroke abutments for sliding of the leg.
 4. A jack according toclaim 3, in which said link device comprises a continuous ordiscontinuous shaft (10) in the tunnel of the base, and connected at itsends to a continuous or discontinuous parallel shaft (9) which passesthrough the leg and/or the slide.
 5. A jack according to claim 2, inwhich the leg (1) has tabs (14) which are folded over the slide to holdit fixed to the leg.
 6. A jack according to claim 2, in which said linkdevice comprises a shaft (9) passing through the leg and/or the slideparallel to said axis and which is attached to the base so as to becapable of pivoting about said axis.
 7. A jack according to claim 6, inwhich said shaft (9) carries springs (13) tending to return the legtowards a position in which the leg is substantially in the middle ofits sliding stroke.
 8. A jack according to claim 7, in which the slide(8) has extensions (8 b, 8 c) outside the leg forming covers for hidingsaid springs.
 9. A jack according to claim 2, in which said link devicecomprises a continuous or discontinuous shaft (10) in the tunnel of thebase, and connected at its ends to a continuous or discontinuousparallel shaft (9) which passes through the leg and/or the slide.
 10. Ajack according to claim 2, in which said block has two walls (8 a, 8 b)constituting stops suitable for coming into abutment against the base todefine the pivot stroke of the leg on the base.
 11. A jack according toclaim 2, and in which said block (8) is in the form of a saddle having arounded and recessed surface (8 e) for pivoting on the rib (5 b) of thebase, and two longitudinal sides (8 a, 8 d) which rise outwardly tocooperate with the base (5 a) by coming into contact therewith to definethe pivot stroke of the leg on the base.
 12. A jack according to claim11, in which the block has two bores (8 g, 8 h) in alignment that opento the outside of the block to receive the ends of two springs (13) andinterconnected by a central bore (8 i) serving as a bearing for a shaft(9) which passes through the aligned bores and which carries thesprings.
 13. A jack according to claim 1, in which the leg (1) has tabs(14) which are folded over the slide to hold it fixed to the leg.
 14. Ajack according to claim 1, in which said link device comprises a shaft(9) passing through the leg and/or the slide parallel to said axis andwhich is attached to the base so as to be capable of pivoting about saidaxis.
 15. A jack according to claim 14, in which said shaft (9) carriessprings (13) tending to return the leg towards a position in which theleg is substantially in the middle of its sliding stroke.
 16. A jackaccording to claim 15, in which the slide (8) has extensions (8 b, 8 c)outside the leg forming covers for hiding said springs.
 17. A jackaccording to claim 1, in which said link device comprises a continuousor discontinuous shaft (10) in the tunnel of the base, and connected atits ends to a continuous or discontinuous parallel shaft (9) whichpasses through the leg and/or the slide.
 18. A jack according to claim1, in which said block has two walls (8 a, 8 b) constituting stopssuitable for coming into abutment against the base to define the pivotstroke of the leg on the base.
 19. A jack according to claim 1, and inwhich said block (8) is in the form of a saddle having a rounded andrecessed surface (8 e) for pivoting on the rib (5 b) of the base, andtwo longitudinal sides (8 a, 8 d) which rise outwardly to cooperate withthe base (5 a) by coming into contact therewith to define the pivotstroke of the leg on the base.
 20. A jack according to claim 19, inwhich the block has two bores (8 g, 8 h) in alignment that open to theoutside of the block to receive the ends of two springs (13) andinterconnected by a central bore (8 i) serving as a bearing for a shaft(9) which passes through the aligned bores and which carries thesprings.